Terminology

PHB: Player’s Handbook, a core rule book, mandatory reading!

PCs: Player characters (Ander, Marta, etc.)
NPCs: Non-player characters (Birin, Saza, etc.)
DM: Dungeon master, the narrator and arbiter
TPK: Total party kill, when all the PCs die
RAW: Rules as written, the literal, strict interpretation of the rules as written in the PHB
PR: Potentiality remnant (in-game artefacts of power)

d8: An eight sided die, the number after the “d” is how many sides it has
2d6: Two, six sided dice, the number before the “d” is the number of dice to roll
1d4+3: One, four sided die, the number after the “+” is a straight addition to the total of the roll

Rolls: The only rolls which aren’t a d20, are damage rolls once you’ve already hit, and class specific hit die
Ability Checks: Checks involving any of the six base stats or specific named skills (Acrobatics, Stealth, etc.), these are usually required when a PC attempts to do something of their own volition
Saving Throws: A special roll derived from the six base stats, however these are usually forced upon the PCs by external threats
Proficiency: The idea that a creature is experienced in the given skill or use of an item, if you are proficient with something, you understand it’s workings or are competent in it’s execution
Proficiency Bonus: Is the abstraction of this knowledge, the addition modifier you make to rolls which involve something a PC is proficient with

Spells: Magical and arcane abilities which certain classes can call upon
Spell Levels: Each spell has a minimum spell level (1-9), a rough indication of how powerful the spell is. The spell level has nothing to do with character level

Spell Slots: Consider these expendable items, like potions. Casters have a finite amount of slots they can expend in order to cast spells. If you want to cast a 2nd Level Spell, you’ll need to expend a 2nd Level Spell Slot. Once it’s expended, you can’t get it back until you restore your slots with a Long Rest or another ability. You can single-use buff some spells by casting them using a higher level slot. Like Spells themselves, Slots have a Level, a rough indication of how much capacity that slot has

Cantrips: These are a very specific kind of spell. Cantrips are a basic, second nature ability of casters who are so connected to the effect, they can cast them at will with no cost. They technically have a “Spell Level” of 0 (zero), thereby not expending any slots

Action: With a capital “A”, Actions are specific, named things you can do in combat. See the printed list of Actions at the next session. Doing any of these uses up your Action in your combat turn. The most frequently used is the “attack Action”
Bonus Action: Some classes allow some specific activities or powers to be used as a Bonus Action. You can do one of these things in addition to your usual Action in your combat turn
Reaction: Every creature also gets a single Reaction to use in their combat turn, the most frequently used is the “Opportunity Attack”

AC: Armor Class, an indicator of how difficult a creature is to hit. A slight misnomer, as the equipped, physically worn armour contributes only a part of this number. Small, agile, or transient creatures may have a higher AC than a walking tank clad in iron

Short Rest: Minimum 1 hour of nothing more strenuous than eating, drinking, or reading. PCs can expend hit die at the end of the rest to heal
Long Rest: Minimum 8 hours of nothing more strenuous than eating, drinking, or reading. PCs can stand watch for a maximum of only 2 hours and still qualify. At the end, all hit points are recovered, and half hit die restored. Only one long rest per day

Terminology

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